@@ -574,6 +574,7 @@ The
.B sloppy
option is an alternative to specifying
.BR mount.nfs " -s " option.
+
.TP 1.5i
.BI xprtsec= policy
Specifies the use of transport layer security to protect NFS network
@@ -607,6 +608,19 @@ option is not specified,
the default behavior depends on the kernel,
but is usually equivalent to
.BR "xprtsec=none" .
+.TP 1.5i
+.B fasc
+Triggers the clearing of the file access cache as soon as the cache
+timestamp becomes older than the user's login time. It is supported
+in kernels 6.4 and later.
+.IP
+NFS servers often refresh their users' group membership at their
+own cadence, which means the NFS client's file access cache can
+become stale if the user's group membership changes on the server
+after they've logged in on the client. To align with the principles
+of the POSIX design, which only refreshes the user's supplementary
+group information upon login, the mechanism uses the user's login
+time to determine whether the file access cache needs to be refreshed.
.SS "Options for NFS versions 2 and 3 only"
Use these options, along with the options in the above subsection,
for NFS versions 2 and 3 only.
Add an option that triggers the clearing of the file access cache as soon as the cache timestamp becomes older than the user's login time. Signed-off-by: Chengen Du <chengen.du@canonical.com> --- utils/mount/nfs.man | 14 ++++++++++++++ 1 file changed, 14 insertions(+)